Hybrid bonding structures and semiconductor devices including the same

ABSTRACT

A hybrid bonding structure and a semiconductor including the hybrid bonding structure are provided. The hybrid bonding structure includes a solder ball and a solder paste bonded to the solder ball. The solder paste may include solder particles including at least one of In, Zn, SnBiAg alloy, or SnBi alloy, and ceramic particles. The solder paste may include a flux. The solder particles may include Sn(42.0 wt %)-Ag(0.4 wt %)-Bi(57.5−X) wt %, and the ceramic particles include CeO2(X) wt %, where 0.05≤X≤0.1.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based on and claims priority under 35 U.S.C. § 119to Korean Patent Application No. 10-2020-0114855, filed on Sep. 8, 2020,in the Korean Intellectual Property Office, the disclosure of which isincorporated by reference herein in its entirety.

BACKGROUND 1. Field

The present disclosure relates to hybrid bonding structures configuredto bond at a low temperature and semiconductor devices including one ormore of such hybrid bonding structures, and methods of making same.

2. Description of the Related Art

In semiconductor packaging, methods of bonding elements to each other byusing metal alloys having various melting temperatures are used. One ofthese bonding methods is soldering. An SAC-based solder composed of analloy of metal materials such as tin (Sn), silver (Ag), and copper (Cu)is a representative example of a material commonly used for soldering.

The melting point of the SAC-based solder is in the range of about 200°C. to about 230° C., and thus, when the SAC-based solder is applied to ahighly integrated and thin semiconductor package, a substrate thereofmay be bent or stretched depending on a process temperature range. Inthis case, damage to a solder bonding portion occurs as forces inopposite directions, such as tensile stress and compressive stress, areapplied to the top and bottom of the substrate.

SUMMARY

Provided are hybrid bonding structures configured to bond at lowtemperatures.

Provided are semiconductor devices including hybrid bonding structuresconfigured to bond at low temperatures.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented example embodiments of thedisclosure.

According to some example embodiments, a hybrid bonding structure mayinclude a solder ball and a solder paste bonded to the solder ball. Thesolder paste may include solder particles, the solder particlesincluding at least one of In, Zn, SnBiAg alloy, or SnBi alloy, a flux,and ceramic particles. A boundary area between the solder ball and thesolder paste may have a modulus of elasticity in a range of about 42.0GPa to about 45.0 GPa.

The ceramic particles may include at least one of La₂O₃, CeO₂, SiC,ZrO₂, TiO₂, Y₂O₃, or AlN.

The solder particles may include Sn(42.0 wt %)-Ag(0.4 wt %)-Bi(57.5−X)wt %, and the ceramic particles include CeO₂(X) wt %, where 0.05≤X≤0.1.

The ceramic particles may be included in an amount of about 0.05 wt % toabout 0.1 wt % of a total mass of the solder paste.

The hybrid bonding structure may have a Poisson's ratio in a range ofabout 0.31 to about 0.35.

The hybrid bonding structure may have a coefficient of thermal expansionin a range of about 14 μm/(m·K) to about 40 μm/(m·K).

The ceramic particles may include one or more surfaces having etchedirregularities thereof.

The ceramic particles may each include a metal thin film configured toform an intermetallic compound on one or more surfaces of the ceramicparticles.

The metal thin film may include at least one of Au, Ag, Sn, In, Cu, orNi.

The solder ball may include at least one of Sn—Ag—Cu alloy, Sn—Bi alloy,Sn—Bi—Ag alloy, or Sn—Ag—Cu—Ni alloy.

According to some example embodiments, a semiconductor device mayinclude a printed circuit board, a semiconductor chip, and a hybridbonding structure between the printed circuit board and thesemiconductor chip. The hybrid bonding structure may include a solderball and a solder paste bonded to the solder ball. The solder paste mayinclude solder particles, the solder particles including at least one ofIn, Zn, SnBiAg alloy, or SnBi alloy, a flux, and ceramic particles. Aboundary area between the solder ball and the solder paste may have amodulus of elasticity in a range of about 42.0 GPa to about 45.0 GPa.

The ceramic particles may include at least one of La₂O₃, CeO₂, SiC,ZrO₂, TiO₂, Y₂O₃, or AlN.

The solder particles may include Sn(42.0 wt %)-Ag(0.4 wt %)-Bi(57.5−X)wt %, and the ceramic particles include CeO₂(X) wt %, where 0.05≤X≤0.1.

The ceramic particles may include about 0.05 wt % to about 0.1 wt % of atotal mass of the solder paste.

The hybrid bonding structure may have a Poisson's ratio in a range ofabout 0.31 to about 0.35.

The hybrid bonding structure may have a coefficient of thermal expansionin a range of about 14 μm/(m·K) to about 40 μm/(m·K).

The ceramic particles may include one or more surfaces having etchedirregularities thereof.

The ceramic particles may each include a metal thin film configured toform an intermetallic compound on one or more surfaces of the ceramicparticles.

The metal thin film may include at least one of Au, Ag, Sn, In, Cu, orNi.

The solder ball may include at least one of Sn—Ag—Cu alloy, Sn—Bi alloy,Sn—Bi—Ag alloy, or Sn—Ag—Cu—Ni alloy.

An electronic device may include the semiconductor device.

According to some example embodiments, a hybrid bonding structure mayinclude a solder ball; and a solder paste bonded to the solder ball. Thesolder paste may include solder particles, the solder particlesincluding at least one of In, Zn, SnBiAg alloy, or SnBi alloy, a flux,and ceramic particles. The ceramic particles may include at least one ofLa₂O₃, CeO₂, SiC, ZrO₂, TiO₂, Y₂O₃, or AlN.

The ceramic particles may include one or more surfaces having etchedirregularities thereof.

The ceramic particles may each include a metal thin film configured toform an intermetallic compound on one or more surfaces of the ceramicparticles.

The metal thin film may include at least one of Au, Ag, Sn, In, Cu, orNi.

The solder ball may include at least one of Sn—Ag—Cu alloy, Sn—Bi alloy,Sn—Bi—Ag alloy, or Sn—Ag—Cu—Ni alloy.

According to some example embodiments, a method may include forming ametal pad on a semiconductor chip, placing a solder ball on the metalpad such that the solder ball is attached to the metal pad, applying asolder paste to a substrate based on using a mask, wherein the solderpaste includes solder particles, the solder particles including at leastone of In, Zn, SnBiAg alloy, or SnBi alloy, a flux, and ceramicparticles, bringing the solder ball into contact with the solder paste,and at least partially melting the solder paste to cause the solderpaste to become bonded to the solder ball to form a semiconductordevice, such that a boundary area between the solder ball and the solderpaste bonded thereto has a modulus of elasticity in a range of about42.0 GPa to about 45.0 GPa.

The method may further include manufacturing an electronic device thatincludes the semiconductor device.

The ceramic particles may include at least one of La₂O₃, CeO₂, SiC,ZrO₂, TiO₂, Y₂O₃, or AlN.

The solder particles may include Sn(42.0 wt %)-Ag(0.4 wt %)-Bi(57.5−X)wt %, and the ceramic particles include CeO₂(X) wt %, where 0.05≤X≤0.1.

The ceramic particles may be included in an amount of about 0.05 wt % toabout 0.1 wt % of a total mass of the solder paste.

The ceramic particles may include one or more surfaces having etchedirregularities thereof.

The ceramic particles may each include a metal thin film configured toform an intermetallic compound on one or more surfaces of the ceramicparticles.

The metal thin film may include at least one of Au, Ag, Sn, In, Cu, orNi.

The solder ball may include at least one of Sn—Ag—Cu alloy, Sn—Bi alloy,Sn—Bi—Ag alloy, or Sn—Ag—Cu—Ni alloy.

According to some example embodiments, a solder paste composition mayinclude solder particles, the solder particles including at least one ofIn, Zn, SnBiAg alloy, or SnBi alloy; and ceramic particles. The ceramicparticles may include at least one of La₂O₃, CeO₂, SiC, ZrO₂, TiO₂,Y₂O₃, or AlN.

The ceramic particles may include one or more surfaces having etchedirregularities thereof.

The ceramic particles may each include a metal thin film configured toform an intermetallic compound on one or more surfaces of the ceramicparticles.

The metal thin film may include at least one of Au, Ag, Sn, In, Cu, orNi.

The solder paste composition may further include a flux.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of certainembodiments of the disclosure will be more apparent from the followingdescription taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 is a schematic view of a hybrid bonding structure according tosome example embodiments;

FIG. 2 is a schematic view of a semiconductor device including a hybridbonding structure according to some example embodiments;

FIG. 3 is a view illustrating a boundary area of a hybrid bondingstructure according to some example embodiments;

FIG. 4 illustrates a ball shear test (BST) strength according to thecontent of CeO₂ ceramic particles of a hybrid bonding structureaccording to some example embodiments;

FIG. 5 is a graph showing a drop shock test (DST) failure percentage ofa bonding structure according to the number of thermal cycles;

FIG. 6 is a graph showing a joint shift teat (JST) strain rate accordingto the number of thermal cycles;

FIGS. 7, 8, 9, 10, and 11 are views illustrating a method ofmanufacturing a hybrid bonding structure, according to some exampleembodiments;

FIG. 12 is a flowchart illustrating a method of manufacturing asemiconductor device, according to some example embodiments; and

FIG. 13 is a schematic diagram of an electronic device according to someexample embodiments.

DETAILED DESCRIPTION

Reference will now be made in detail to example embodiments, some ofwhich are illustrated in the accompanying drawings, wherein likereference numerals refer to like elements throughout. In this regard,some example embodiments may have different forms and should not beconstrued as being limited to the descriptions set forth herein.Accordingly, the example embodiments are merely described below, byreferring to the figures, to explain aspects. As used herein, the term“and/or” includes any and all combinations of one or more of theassociated listed items. Expressions such as “at least one of,” whenpreceding a list of elements, modify the entire list of elements and donot modify the individual elements of the list.

It will be understood that elements and/or properties thereof may berecited herein as being “the same” or “equal” as other elements, and itwill be further understood that elements and/or properties thereofrecited herein as being “the same” as or “equal” to other elements maybe “the same” as or “equal” to or “substantially the same” as or“substantially equal” to the other elements and/or properties thereof.Elements and/or properties thereof that are “substantially the same” asor “substantially equal” to other elements and/or properties thereofwill be understood to include elements and/or properties thereof thatare the same as or equal to the other elements and/or properties thereofwithin manufacturing tolerances and/or material tolerances. Elementsand/or properties thereof that are the same or substantially the same asother elements and/or properties thereof may be structurally the same orsubstantially the same, functionally the same or substantially the same,and/or compositionally the same or substantially the same.

It will be understood that elements and/or properties thereof describedherein as being the “substantially” the same encompasses elements and/orproperties thereof that have a relative difference in magnitude that isequal to or less than 10%. Further, regardless of whether elementsand/or properties thereof are modified as “substantially,” it will beunderstood that these elements and/or properties thereof should beconstrued as including a manufacturing or operational tolerance (e.g.,±10%) around the stated elements and/or properties thereof.

When the terms “about” or “substantially” are used in this specificationin connection with a numerical value, it is intended that the associatednumerical value include a tolerance of ±10% around the stated numericalvalue. When ranges are specified, the range includes all valuestherebetween such as increments of 0.1%.

Hereinafter, hybrid bonding structures, solder paste compositions,semiconductor devices including the same and/or electronic devicesincluding the same according to some example embodiments will bedescribed in detail with the accompanying drawings. In the drawings,like reference numerals refer to like elements, and the size of eachelement may be exaggerated for clarity and convenience of explanation.It will be understood that, although the terms first, second, etc. maybe used herein to describe various elements, these elements should notbe limited by these terms. These terms are only used to distinguish oneelement from another.

As used herein, the singular forms “a,” “an,” and “the” may be intendedto include the plural forms as well, unless the context clearlyindicates otherwise. In addition, when an element is referred to as“comprising” or “including” a component, it does not preclude anothercomponent but may further include the other component unless the contextclearly indicates otherwise. In addition, in the drawings, the size andthickness of each element may be exaggerated for clarity of explanation.It will be understood that when a certain material layer is referred toas being “on” a substrate or another layer, it can be directly on thesubstrate or the other layer, or an intervening third layer and/or spacemay be present such that the certain material layer may be indirectly onthe substrate or the other layer so as to be isolated from directcontact with the substrate or the other layer. Also, materials includedin layers described in some example embodiments below are only providedas examples, and other materials may be used.

The term “unit”, “module” or the like means a unit configured to processat least one function or operation, and this may be implemented inhardware or software, or implemented by combining hardware and software.

The particular implementations shown and described herein areillustrative examples and are not intended to otherwise limit the scopeof the present inventive concepts in any way. For the sake of brevity,conventional electronics, control systems, software development andother functional aspects of the systems may not be described in detail.Furthermore, the connecting lines, or connecting member shown in thevarious figures presented are intended to represent example functionalrelationships and/or physical or circuit connections between the variouselements, and many alternative or additional functional relationships,physical connections or circuit connections may be present in apractical device.

The use of the terms “the” and similar referents in the context ofdescribing the some example embodiments are to be construed to coverboth the singular and the plural.

The steps of all methods described herein can be performed in anysuitable order unless otherwise indicated herein or otherwise clearlycontradicted by context. The use of any and all examples, or examplelanguage (e.g., “such as”) provided herein, is intended merely to betterilluminate the inventive concepts and does not pose a limitation on thescope of the inventive concepts unless otherwise claimed.

FIG. 1 is a schematic view of a hybrid bonding structure according tosome example embodiments.

The hybrid bonding structure 100 includes a solder ball 110 and a solderpaste 130 bonded (e.g., adhered, affixed, etc.) to the solder ball 110.

The solder ball 110 may include, for example, at least one alloyselected from the group consisting of Sn—Ag—Cu alloy, Sn—Bi alloy,Sn—Bi—Ag alloy, or Sn—Ag—Cu—Ni alloy. In some example embodiments, thesolder ball 110 may include, at least one of Sn—Ag—Cu alloy, Sn—Bialloy, Sn—Bi—Ag alloy, or Sn—Ag—Cu—Ni alloy. The solder ball 110 mayinclude, for example, at least one of Sn—Ag(0.3˜3)-Cu(0.1˜1),Sn—Bi(35˜75), Sn—Bi(35˜75)-Ag(0.1˜20), orSn—Ag(0.5˜5)-Cu(0.1˜2)-Ni(0.05˜0.1). For example, when the solder ball110 is composed of a Sn—Ag—Cu alloy, the solder ball 110 may includeSAC305 (Sn-3.0Ag-0.5Cu), SAC205 (Sn-2.0Ag-0.5Cu), or the like.

The solder paste 130 may include solder particles 131, flux 132, andceramic particles 133. The solder particles 131 may be the maincomponent, and the flux 132 and the ceramic particles 133 may beauxiliary components. In some example embodiments, the flux 132 may beomitted. In some example embodiments, some or all of the solder paste130, including the solder particles 131 according to any of the exampleembodiments and ceramic particles 133 according to any of the exampleembodiments, and including or excluding the flux 132 according to any ofthe example embodiments, may be referred to herein as a solder pastecomposition. It will be understood that all descriptions of the solderpaste 130, including at least the solder particles 131 and ceramicparticles 133, according to any of the example embodiments may apply toa solder paste composition that includes at least the solder particles131 and ceramic particles 133 and may comprise, with or without the flux132, the solder paste 130.

The solder particles 131 may include, for example, at least one of In,Zn, SnBiAg alloy, or SnBi alloy. The solder particles 131 may include,for example, Sn58Bi. The solder particles 131 may have diameters in therange of, for example, about 20 μm to about 45 μm.

The flux 132 may include, for example, a water-soluble flux or afat-soluble flux. The flux 132 may include at least one selected fromthe group consisting of a rosin-based flux, a resin-based flux, and anorganic acid-based flux. However, the flux is not limited thereto.

The ceramic particles 133 may have a content in the range of, forexample, about 0.05 wt % to about 0.1 wt %. Restated, the ceramicparticles 133 may be included in the solder past in an amount of about0.05 wt % to about 0.1 wt % as a proportion of a total mass or weight ofthe solder paste. The terms “wt %” and “w %” may be used interchangeablyand may refer to a weight percent as a proportion of a total mass orweight of the solder paste. The ceramic particles 133 may include, forexample, at least one of La₂O₃, CeO₂, SiC, ZrO₂, TiO₂, Y₂O₃, or AlN. Forexample, the solder particles 131 may include Sn57.5Bi0.4Ag and theceramic particles 133 may include 0.1 CeO₂. For example, the solderparticles 131 may include Sn(42.0 w %)-Bi(57.5 w %)-Ag(0.4 w %), and theceramic particles 133 may include CeO₂ (0.1 w %). This is only anexample, and various composition ratios are possible. For example, thesolder particles 131 may include Sn(42.0 w %)-Ag(0.4 w %)-Bi(57.5−X) w%, and the ceramic particles 133 may include CeO₂ (0.05≤X≤0.1) w %.Restated, the solder particles 131 may include Sn(42.0 w %)-Ag(0.4 w%)-Bi(57.5−X) w %, and the ceramic particles 133 may include CeO₂(X) w%, where 0.05≤X≤0.1. The ceramic particles 133 may be surface-treated,such that the ceramic particles 133 have one or more surfaces havingsurface irregularities therein (e.g., trenches extending from an outersurface of a ceramic particle 133 into an interior of the ceramicparticle 133, such that the surface of the ceramic particle 133 hasincreased irregularity or roughness). Surface treatment may be done, forexample, by etching or thin film coating. For example, the ceramicparticles 133 may be surface treated via a plasma surface etchingmethod. Based on having fine irregularities on the surfaces of ceramicparticles 133 through plasma treatment, flowability in the solder pastemay be suppressed.

The ceramic particles 133 may each include a metal thin film 135configured to form an intermetallic compound on one or more surfaces ofthe ceramic particles. The metal thin film may include at least one ofAu, Ag, Sn, In, Cu, or Ni.

The hybrid bonding structure 100 may electrically connect asemiconductor chip to a printed circuit board.

FIG. 2 is a schematic view of a semiconductor device 200 according tosome example embodiments. The semiconductor device 200 may include aprinted circuit board 210, a semiconductor chip 230, and a hybridbonding structure 100 that couples the printed circuit board 210 to thesemiconductor chip 230. The hybrid bonding structure 100 may be a hybridbonding structure according to any of the example embodiments, forexample including a solder ball and a solder paste bonded to the solderball.

The hybrid bonding structure 100 may be configured to have a modulus ofelasticity in the range of about 42.0 GPa to about 45.0 GPa. A boundaryarea A between a solder ball 110 and a solder paste 130 may have amodulus of elasticity in the range of about 42.0 GPa to about 45.0 GPa.

FIG. 3 is a view illustrating a boundary area of a hybrid bondingstructure according to some example embodiments. Referring to FIG. 3,the boundary area A may represent an area including, for example, abonding boundary line 150 at cross-sections of the solder ball 110 andthe solder paste 130. The cross-sections represent cross-sections of thesolder ball 110 and the solder paste 130 cut in a vertical direction.For example, when a point C, at which a line B crossing the center ofthe solder ball 110 in the vertical direction and the bonding boundaryline 150 intersect with each other, is referred to as a boundaryreference point, the boundary area A may represent a rectangular areawithin a range of about 5 μm in each of an upward direction and adownward direction and about 25 μm in each of a left direction and aright direction based on the boundary reference point. However, theboundary area A is not limited thereto and may be defined as variousareas including a boundary line between the solder ball 110 and thesolder paste 130.

The hybrid bonding structure 100 may be configured to have, for example,a Poisson's ratio in the range of about 0.31 to about 0.35 in theboundary area A. The Poisson's ratio may represent a strain rate when anexternal force is applied to the hybrid bonding structure 100.

The hybrid bonding structure 100 may be configured to have, for example,a coefficient of thermal expansion (CTE) in the range of about 14μm/(m·K) to about 40 μm/(m·K) in the boundary area A.

When the difference in physical properties between the solder ball 110and the solder paste 130 is large, a bonding force at the boundary areaA between the solder ball 110 and the solder paste 130 may be weak andthe hybrid bonding structure 100 may be easily broken by externalimpact. The hybrid bonding structure 100 according to some exampleembodiments may increase bonding force and decrease brittleness byadjusting at least one of a modulus of elasticity, a Poisson's ratio, ora CTE of each of the solder ball 110 and the solder paste 130.

The hybrid bonding structure 100 may be used as a low-temperaturebonding material applied to (e.g., included in), for example, a dataserver, a notebook computer, a mobile phone, and a TV. As a substratebecomes thinner and a semiconductor device becomes smaller, thesemiconductor device may be affected by temperature. Accordingly, astructure capable of being bonded (e.g., configured to be bonded) to asemiconductor device at a low temperature to have a reduced effect onthe semiconductor device or to affect the semiconductor device as littleas possible may be employed as a bonding structure for bonding of thesemiconductor device. By the way, for example, Sn58Bi is alow-temperature bonding material, but has problems such as brittlefracture and thermal deformation.

For example, in the case of bonding using an SAC solder ball and aSn58Bi solder paste, fracture occurs mainly at the boundary between theSAC solder ball and the Sn58Bi solder paste during tests such asdropping or thermal shock. The reason is that physical properties suchas CTE, modulus of elasticity, and Poisson's ratio are significantlydifferent between the SAC solder ball and the Sn58Bi solder paste andthe Sn58Bi solder paste has brittleness.

In some example embodiments, the hybrid bonding structure 100 accordingto some example embodiments may be bonded at a low temperature and mayreduce a defect rate by adjusting at least one of a modulus ofelasticity, a Poisson's ratio, or a CTE and have strong brittlenessproperties.

The solder paste 130 may include, for example, a material having amelting point of about 200° C. or less. The solder paste 130 mayinclude, for example, a material having a melting point of about 150° C.or less (e.g., about 130° C. to about 150° C.). In addition, the solderpaste 130 may include ceramic particles 133 to alleviate brittleness,and the content of the ceramic particles 133 may be adjusted.

FIG. 4 illustrates a ball shear (BS) strength according to the contentof CeO₂ ceramic particles. For example, FIG. 4 illustrates a BS strengthaccording to a content X of CeO₂ ceramic particles added toSn(57.5−X)Bi0.4Ag solder particles. The BS strength may represent shearstress strength. When the content X of the CeO₂ ceramic particles isabout 0.1 wt %, a relatively high shear stress strength is shown. Whenthe content X of the CeO₂ ceramic particles is about 0.3 wt %, the shearstress strength decreases, and when the content X of the CeO₂ ceramicparticles is about 0.5 wt %, the shear stress strength increases again.For example, when the content X of the CeO₂ ceramic particles is about0.1 wt %, a BS strength of approximately 440 gf may be obtained. In thehybrid bonding structure 100 according to some example embodiments, theceramic particles 133 may have a content greater than 0 and less than orequal to about 0.1 wt %. In some example embodiments, the ceramicparticles 133 may have a content in the range of about 0.05 wt % toabout 0.1 wt %. Therefore, the BS strength may be increased.

FIG. 5 is a graph showing a drop shock test (DST) failure percentageaccording to the number of thermal cycles. The graph of FIG. 5 showsresults of performing thermal cycle (T/C) evaluation to confirm thethermal shock reliability of a semiconductor package. The T/C evaluationis an operation of performing a drop shock test on a semiconductorpackage while repeatedly changing the temperature from low to high. Amechanical strength may be evaluated through the drop shock test. Forreference, in the T/C evaluation, a temperature range was about −40° C.to about 125° C. A comparative example shows a case where the solderpaste includes Sn57.6Bi0.4Ag.

The failure percentage increases as the number of thermal cyclesincreases. According to some example embodiments, a hybrid bondingstructure including 0.1 wt % of CeO₂ (e.g., wherein the solder pasteincludes solder particles including Sn(42.0 wt %)-Ag(0.4 wt%)-Bi(57.5−X) wt %, and the ceramic particles include CeO₂(X) wt %,where X=0.1) has a lower failure rate at the same number of cyclescompared to the comparative example (e.g., wherein the solder pasteincludes Sn(57.6)Bi0.4Ag solder particles). The mechanical strength ofthe hybrid bonding structure according to some example embodiments isrelatively high.

FIG. 6 is a graph showing results of a joint shift test (JST) for ahybrid bonding structure. FIG. 6 illustrates a JST strain rate accordingto the number of thermal cycles. In this case, a glass chip forevaluation was prepared, and the strain (i.e., deformation) of a joint(i.e., a bonding portion) during T/C evaluation was observed.

A comparative example shows a case where the solder paste includesSn57.6Bi0.4Ag. In addition, a result of a JST when about 0.1 wt % ofCeO₂ is included (e.g., wherein the solder paste of the hybrid bondingstructure includes solder particles including Sn(42.0 wt %)-Ag(0.4 wt%)-Bi(57.5−X) wt %, and the ceramic particles include CeO₂(X) wt %,where X=0.1), and a result of a JST when about 0.05 wt % of CeO₂ areincluded (e.g., wherein the solder paste of the hybrid bonding structureincludes solder particles including Sn(42.0 wt %)-Ag(0.4 wt%)-Bi(57.5−X) wt %, and the ceramic particles include CeO₂(X) wt %,where X=0.05) are shown. Compared to the comparative example, the casewhere ceramic particles are included, according to some exampleembodiments, has a relatively small strain rate. In addition, the casewhere about 0.05 wt % of CeO₂ is included has less strain than the casewhere about 0.1 wt % of CeO₂ is included.

The table below shows the number (e.g., quantity) of bonding portions inwhich strain (i.e., deformation) has occurred according to the number ofthermal cycles.

TABLE 1 Comparative example Number of cycles (Sn57.6Bi0.4Ag) CeO₂ 0.1 wt% CeO₂ 0.05 wt % 10 0 0 0 20 0 0 0 30 5 0 0 40 13 4 0 45 8 0 2 50 3 13 455 13 16 22 60 6 5 1 65 2 4 7

The hybrid bonding structure according to some example embodiments maybe bonded at a low-temperature and reduce a defect rate of a bondingportion caused by thermal deformation. In addition, compared to aSn58Bi-based solder of the comparative example, the hybrid bondingstructure according to some example embodiments may improve mechanicalproperties, for example, toughness.

In the hybrid bonding structure according to some example embodiments,when the solder paste includes ceramic particles having a content in therange of about 0.05 wt % to about 0.1 wt %, a defect rate due to thewettability and poor application of the solder paste may be reduced.

In order to uniformly disperse the ceramic particles in the solder pasteand improve wettability, the ceramic particles may be surface-treated,such that the ceramic particles have one or more surfaces having surfaceirregularities therein (e.g., trenches extending from an outer surfaceof a ceramic particle into an interior of the ceramic particle, suchthat the surface of the ceramic particle has increased irregularity).Surface treatment may be done, for example, by etching or thin filmcoating.

For example, for surface treatment of ceramic particles, a plasmasurface etching method may be used. By forming fine irregularities onthe surfaces of ceramic particles through plasma treatment, flowabilityin the solder paste may be suppressed. In some example embodiments, whena thin film coating is applied to ceramic particles, a metal thin film,which is capable of forming an intermetallic compound on the surfaces(e.g., one or more surfaces) of the ceramic particles during a processof bonding solder particles to the surfaces of the ceramic particles,may be formed. Restated, the ceramic particles may each include a metalthin film configured to form an intermetallic compound on one or moresurfaces of the ceramic particles. The intermetallic compound representsa compound composed of two or more metals. A common alloy has astructure of a solid solution in which a structure of one metal ismaintained and the other metal is randomly substituted. The common alloyis referred to as a solid solution alloy. Even though metalsconstituting the solid solution alloy are the same, the composition ofthe solid solution alloy may be made in various ratios, although thereis a certain width. The intermetallic compound is a compound having acrystal structure different from that of the original metal. Thecomposition of the intermetallic compound may include two or more metalswith a simple integer ratio. The metal thin film may include, forexample, at least one of Au, Ag, Sn, In, Cu, or Ni.

In the hybrid bonding structure according to some example embodiments,ceramic particles may be uniformly dispersed in the solder paste. Duringthe bonding process, mechanical properties may be improved bymaintaining a dispersed state of the ceramic particles in the solderpaste.

FIGS. 7, 8, 9, 10, and 11 are views illustrating a method ofmanufacturing a semiconductor device, according to some exampleembodiments. FIG. 12 is a flowchart illustrating a method ofmanufacturing a semiconductor device, according to some exampleembodiments.

Referring to FIG. 7 and FIG. 12, at S1210 a metal pad 315 may be formedon a semiconductor chip 310 and a solder ball 330 may be arranged (e.g.,placed) on the metal pad 315, for example to directly contact the metalpad. The semiconductor chip 310 may include, for example, a memory chip.The semiconductor chip 310 may include, for example, DRAM or PRAM.Reference numeral 320 denotes a protective film.

Referring to FIG. 8 and FIG. 12, at S1220 the solder ball 330 may beattached to (and may direct contact) the metal pad 315. The solder ball330 may include any of the solder balls according to any of the exampleembodiments. The solder ball 330 may include, for example, at least onealloy selected from the group consisting of Sn—Ag—Cu alloy, Sn—Bi alloy,Sn—Bi—Ag alloy, and Sn—Ag—Cu—Ni alloy. In some example embodiments, thesolder ball 330 may include, at least one of Sn—Ag—Cu alloy, Sn—Bialloy, Sn—Bi—Ag alloy, or Sn—Ag—Cu—Ni alloy.

Referring to FIG. 9 and FIG. 12, at S1230 a solder paste 360 may beapplied to a substrate, including for example a printed circuit board345 but not limited thereto, based on using a mask 340, for example suchthat one or more discrete instances of solder paste are on one or morelimited portions of a surface of the substrate (e.g., printed circuitboard 345) and one or more remainder portions of said surface of thesubstrate are exposed from the solder paste 360, for example as shown inFIG. 9. As shown in FIG. 9, when multiple instances of solder paste 360are applied to the substrate (e.g., printed circuit board 345), themultiple instances of solder paste 360 are isolated from direct contactwith each other, based on the solder paste 360 being applied to thesubstrate based on using the mask 340. The solder paste 360 may includeany of the solder pastes according to any of the example embodiments. Asa method of applying the solder paste 360, for example, a stencilprinting method may be used. The printed circuit board 345 may includean electrode 350 in addition to a wire required to supply power or athin-film-transistor (TFT). The electrode 350 may be formed using aportion of a metal wire formed on the printed circuit board 345, or maybe formed as a metal pad connected to the metal wire. Since the solderpaste 360 is substantially the same as that described with reference toFIG. 1, a detailed description thereof is omitted here.

An example of a process of manufacturing the solder paste 360 will bedescribed below. A solder paste manufacturing method may includepreparing a solder solution by putting solder particles in an organicsolvent. After a mixed solution is prepared by putting ceramic particlesin the solder solution, the ceramic particles may be dispersed using,for example, ultrasonic waves. Then, the mixed solution is put into aball mill equipment, and a rotating drum is rotated at high speed. Themixed solution in which the ceramic particles are dispersed is retrievedand dried. Then, a solder paste may be prepared by mixing a flux withthe solder particles and the ceramic particles. The flux may preventoxidation of the solder particles. The flux may include a materialhaving good thermal decomposition so that it is capable of beingdecomposed during a low-temperature bonding process.

The flux may include a water-soluble flux or a fat-soluble flux. Theflux may include at least one selected from the group consisting of arosin-based flux, a resin-based flux, and an organic acid-based flux.However, the flux is not limited thereto. In some example embodiments,the flux may include at least one of a rosin-based flux, a resin-basedflux, or an organic acid-based flux.

In some example embodiments, based on adding ceramic particles to thesolder paste, the crystal grains of the solder particles may be refined,and the growth of the intermetallic compound may be suppressed, therebyimproving mechanical properties.

Referring to FIG. 10 and FIG. 12, at S1240 the solder ball 330 of FIG. 8may be brought into contact with the solder paste 360. In addition,referring to FIG. 11 and FIG. 12, at S1250 the solder paste 360 may beat least partially melted through a reflow process to be bonded to thesolder ball 330 to form the hybrid bonding structure 335 that bonds thesemiconductor chip 310 to the circuit board 345 at S1250, therebyforming a semiconductor device according to some example embodiments,thereby forming a semiconductor device (which may be the semiconductordevice according to any of the example embodiments), such that aboundary area between the solder ball and the solder paste bondedthereto has a modulus of elasticity in a range of about 42.0 GPa toabout 45.0 GPa. The melting temperature of the solder paste 360 may be,for example, 150° C. or less. The melting temperature of the solderpaste 360 may have, for example, a range of about 130° C. to about 150°C.

The hybrid bonding structure may be hardened during a cooling period inthe reflow process.

A semiconductor device according to some example embodiments may includean active device or a passive device. The semiconductor device may behighly integrated on one substrate. In this case, a low-temperaturebonding material is required to reduce defects and performancedegradation due to thermal damage to the semiconductor device. Thelow-temperature bonding material may be applied to a semiconductordevice according to some example embodiments. For example, thesemiconductor device may include a memory semiconductor package ormodule used in a data server and a mobile notebook.

In some example embodiments, the semiconductor device according to someexample embodiments may be applied to a flexible display, a wearabledisplay, a foldable display, a stretchable display, and the like.

FIG. 13 is a schematic diagram of an electronic device according to someexample embodiments.

Referring to FIG. 13, the electronic device 1300 may include a processor1320, a memory 1330, and a display device 1340 which are electricallyconnected to each other through a bus 1310. The processor 1320, thememory 1330, and/or the display device 1340 may include any one of thesemiconductor devices according to any of the example embodimentsherein. In some example embodiments the display device 1340 may be aflexible display, a wearable display, a foldable display, a stretchabledisplay, and the like according to any of the example embodiments. Thememory 1330, which is a non-transitory computer-readable medium, maystore an instruction program. The processor 1320 may execute a storedinstruction program to perform one or more functions. The processor 1320may generate output (e.g., an image to be displayed on the displaydevice 1340) based on such processing.

The memory 1330 may be a non-transitory computer readable medium and maystore a program of instructions. The memory 1330 may be a nonvolatilememory, such as a flash memory, a phase-change random access memory(PRAM), a magneto-resistive RAM (MRAM), a resistive RAM (ReRAM), or aferro-electric RAM (FRAM), or a volatile memory, such as a static RAM(SRAM), a dynamic RAM (DRAM), or a synchronous DRAM (SDRAM). Theprocessor 1320 may execute the stored program of instructions to performone or more functions. The processor 1320 may include processingcircuitry such as hardware including logic circuits; a hardware/softwarecombination such as a processor executing software; or a combinationthereof. For example, the processing circuitry more specifically mayinclude, but is not limited to, a central processing unit (CPU), anarithmetic logic unit (ALU), a digital signal processor, amicrocomputer, a field programmable gate array (FPGA), a System-on-Chip(SoC), a programmable logic unit, a microprocessor, application-specificintegrated circuit (ASIC), etc. The processor 1320 may be configured togenerate an output (e.g., an electrical signal) based on suchprocessing.

Referring to FIG. 12 and FIG. 13, at S1260 an electronic device 1300that includes the semiconductor device formed at S1250 may manufactured.For example, the semiconductor device may be incorporated (e.g.,applied) into one or more elements of the electronic device 1300 tocomplete manufacturing of the electronic device 1300. Said one or moreelements may include, for example, a display device 1340, a memory 1330,or a processor 1320. Said incorporation may include, as part of themanufacturing of the electronic device 1300, adhesion of thesemiconductor device to one or more other components of the one or moreelements via an adhesive, soldering of electrical connections betweenthe semiconductor device and one or more other components of the one ormore elements, or the like, in order to at least partially completeassembly of said one or more elements and/or assembly of said electronicdevice 1300.

The above-described example embodiments are merely examples, and variousmodifications and equivalent other example embodiments may be made fromthe above-described example embodiments by those of ordinary skill inthe art. Therefore, a true technical protection scope according to someexample embodiments has to be determined by the inventive conceptsdescribed in the following claims.

Some example embodiments provide a hybrid bonding structure capable ofbonding at a low temperature. By bonding a printed circuit board to asemiconductor chip at a low temperature by using a solder pasteincluding ceramic particles, the deformation of a semiconductor packagedue to a high temperature may be reduced. In addition, the hybridbonding structure according to some example embodiments may improvebrittleness (e.g., reduce brittleness), thereby reducing package defectsof a semiconductor device.

It should be understood that example embodiments described herein shouldbe considered in a descriptive sense only and not for purposes oflimitation. Descriptions of features or aspects within each exampleembodiment should typically be considered as available for other similarfeatures or aspects in other embodiments. While one or more exampleembodiments have been described with reference to the figures, it willbe understood by those of ordinary skill in the art that various changesin form and details may be made therein without departing from thespirit and scope as defined by the following claims.

1. A hybrid bonding structure, comprising: a solder ball; and a solderpaste bonded to the solder ball, wherein the solder paste includessolder particles, the solder particles including at least one of In, Zn,SnBiAg alloy, or SnBi alloy, a flux, and ceramic particles, and whereina boundary area between the solder ball and the solder paste has amodulus of elasticity in a range of about 42.0 GPa to about 45.0 GPa. 2.The hybrid bonding structure of claim 1, wherein the ceramic particlesinclude at least one of La₂O₃, CeO₂, SiC, ZrO₂, TiO₂, Y₂O₃, or AlN. 3.The hybrid bonding structure of claim 1, wherein the solder particlesinclude Sn(42.0 wt %)-Ag(0.4 wt %)-Bi(57.5−X) wt %, and the ceramicparticles include CeO₂(X) wt %, where 0.05≤X≤0.1.
 4. The hybrid bondingstructure of claim 1, wherein the ceramic particles are included in anamount of about 0.05 wt % to about 0.1 wt % of a total mass of thesolder paste.
 5. The hybrid bonding structure of claim 1, wherein thehybrid bonding structure has a Poisson's ratio in a range of about 0.31to about 0.35.
 6. The hybrid bonding structure of claim 1, wherein thehybrid bonding structure has a coefficient of thermal expansion in arange of about 14 μm/(m·K) to about 40 μm/(m·K).
 7. The hybrid bondingstructure of claim 1, wherein the ceramic particles include one or moresurfaces having etched irregularities thereof.
 8. The hybrid bondingstructure of claim 1, wherein the ceramic particles each include a metalthin film configured to form an intermetallic compound on one or moresurfaces of the ceramic particles.
 9. The hybrid bonding structure ofclaim 8, wherein the metal thin film includes at least one of Au, Ag,Sn, In, Cu, or Ni.
 10. The hybrid bonding structure of claim 1, whereinthe solder ball includes at least one of Sn—Ag—Cu alloy, Sn—Bi alloy,Sn—Bi—Ag alloy, or Sn—Ag—Cu—Ni alloy.
 11. A semiconductor device,comprising: a printed circuit board; a semiconductor chip; and a hybridbonding structure between the printed circuit board and thesemiconductor chip, wherein the hybrid bonding structure includes asolder ball and a solder paste bonded to the solder ball, wherein thesolder paste includes solder particles, the solder particles includingat least one of In, Zn, SnBiAg alloy, or SnBi alloy, a flux, and ceramicparticles, and wherein a boundary area between the solder ball and thesolder paste has a modulus of elasticity in a range of about 42.0 GPa toabout 45.0 GPa.
 12. The semiconductor device of claim 11, wherein theceramic particles include at least one of La₂O₃, CeO₂, SiC, ZrO₂, TiO₂,Y₂O₃, or AlN.
 13. The semiconductor device of claim 11, wherein thesolder particles include Sn(42.0 wt %)-Ag(0.4 wt %)-Bi(57.5−X) wt %, andthe ceramic particles include CeO₂(X) wt %, where 0.05≤X≤0.1.
 14. Thesemiconductor device of claim 11, wherein the ceramic particles includeabout 0.05 wt % to about 0.1 wt % of a total mass of the solder paste.15. The semiconductor device of claim 11, wherein the hybrid bondingstructure has a Poisson's ratio in a range of about 0.31 to about 0.35.16. The semiconductor device of claim 11, wherein the hybrid bondingstructure has a coefficient of thermal expansion in a range of about 14μm/(m·K) to about 40 μm/(m·K).
 17. The semiconductor device of claim 11,wherein the ceramic particles include one or more surfaces having etchedirregularities thereof.
 18. The semiconductor device of claim 11,wherein the ceramic particles each include a metal thin film configuredto form an intermetallic compound on one or more surfaces of the ceramicparticles.
 19. The semiconductor device of claim 18, wherein the metalthin film includes at least one of Au, Ag, Sn, In, Cu, or Ni.
 20. Thesemiconductor device of claim 11, wherein the solder ball includes atleast one of Sn—Ag—Cu alloy, Sn—Bi alloy, Sn—Bi—Ag alloy, or Sn—Ag—Cu—Nialloy.
 21. An electronic device comprising the semiconductor device ofclaim
 11. 22. A hybrid bonding structure, comprising: a solder ball; anda solder paste bonded to the solder ball, wherein the solder pasteincludes solder particles, the solder particles including at least oneof In, Zn, SnBiAg alloy, or SnBi alloy, a flux, and ceramic particles,the ceramic particles including at least one of La₂O₃, CeO₂, SiC, ZrO₂,TiO₂, Y₂O₃, or AlN. 23-40. (canceled)